{
  // 🎯interface实现接口继承（老语法）
  // interface Point2D { x: number; y: number }
  // // interface Point3D { x: number; y: number; z: number }
  // interface Point3D extends Point2D{
  //     z:number
  // }
  // 🎯type如何实现继承（新语法）
  type Point2D = { x: number; y: number };
  type Point3D = {
    z: number;
  } & Point2D;
  let Point2D: Point2D = {
    x: 100,
    y: 200,
  };
  let Point3D: Point3D = {
    x: 100,
    y: 200,
    z: 100,
  };
  console.log(Point3D);
}
